Sheets, towels, iron
Best Duvet Tog for Summer
3.0–4.5 tog for a warm bedroom. 1 tog or a sheet only if you already sleep hot at 22C. Tog is thermal resistance, not fill glamour.
Updated 27 Aug 2026 · 6 min read · best duvet tog for summer
Tog is a laboratory number, use it anyway
One tog is 0.1 m²K/W of thermal resistance. 4.5 tog is the UK summer default because it was built for houses that are not air-conditioned. 3 tog is the hot-sleeper summer. 1 tog is a decorative layer over a sheet. US shops that refuse tog will print “light” or “summer weight” — look at fill weight instead, as in insert vs comforter weight.
Fill power is loft per ounce, not tog. An 800-fill 250 g insert can match a 600-fill 400 g insert in warmth with less bulk. For summer, you want the loft without the mass.
| Bedroom night temp | Hot sleeper | Cold sleeper |
|---|---|---|
| 23C+ | Sheet or 1 tog | 3 tog |
| 20–22C | 3 tog | 4.5 tog |
| 17–19C | 4.5 tog | 7 tog or 4.5 + a throw |
| Below 17C | You want the [[best-duvet-tog-for-winter|winter tog]] guide | 10.5–13.5 |
Down, wool, or polyester in summer
Down at 700+ fill, light weight, cotton down-proof shell at 300 count: the dry choice. Wool 4.5 tog runs a little heavier and handles humidity. Polyester 4.5 is $40–$70, sleeps damper, and is the guest-room buy. A sewn-through comforter sold as “all season” is not a summer tool; see duvet vs comforter.
Cover and sheets do more than you think
A 4.5 tog under a heavy sateen cover in 600 GSM-adjacent weave sleeps warmer than the same insert under 300-count percale. If you are still hot, change the cloth before you bin a correct tog. Wash the cover weekly if you skip a top sheet.
Questions, answered
- Is 4.5 tog too cold with air-con at 18C?
- Often. Keep a 7 or 9 tog in the cupboard for those weeks, or buy a 4.5 + 9.0 pair you can button. That is an all-seasons set with a real summer half.
- Can I use a winter duvet inside-out in summer?
- No. 13.5 tog is 13.5 tog from both faces. You will kick it off and then get cold at 4am.
- Does tog apply to polyester?
- Yes. Tog is the whole insert’s resistance, not a down-only number. A polyester 4.5 should still test near 4.5; cheap ones vary. Buy a named tog, not “summer feel.”
